/* Library function for scanning an archive file.
Copyright (C) 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
Foundation, Inc.
This file is part of GNU Make.

GNU Make is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3 of the License, or (at your option) any later
version.

GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "make.h"

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#else
#include <sys/file.h>
#endif

#ifndef	NO_ARCHIVES

/* On the sun386i and in System V rel 3, ar.h defines two different archive
   formats depending upon whether you have defined PORTAR (normal) or PORT5AR
   (System V Release 1).  There is no default, one or the other must be defined
   to have a nonzero value.  */

#if (!defined (PORTAR) || PORTAR == 0) && (!defined (PORT5AR) || PORT5AR == 0)
#undef	PORTAR
#define PORTAR 1
#endif

#ifndef WINDOWS32
#  include <ar.h>
#else
/* These should allow us to read Windows (VC++) libraries (according to Frank
 * Libbrecht <frankl@abzx.belgium.hp.com>)
 */
# include <windows.h>
# include <windef.h>
# include <io.h>
# define ARMAG      IMAGE_ARCHIVE_START
# define SARMAG     IMAGE_ARCHIVE_START_SIZE
# define ar_hdr     _IMAGE_ARCHIVE_MEMBER_HEADER
# define ar_name    Name
# define ar_mode    Mode
# define ar_size    Size
# define ar_date    Date
# define ar_uid     UserID
# define ar_gid     GroupID
#endif

/* Cray's <ar.h> apparently defines this.  */
#ifndef	AR_HDR_SIZE
# define   AR_HDR_SIZE	(sizeof (struct ar_hdr))
#endif

/* Takes three arguments ARCHIVE, FUNCTION and ARG.

   Open the archive named ARCHIVE, find its members one by one,
   and for each one call FUNCTION with the following arguments:
     archive file descriptor for reading the data,
     member name,
     member name might be truncated flag,
     member header position in file,
     member data position in file,
     member data size,
     member date,
     member uid,
     member gid,
     member protection mode,
     ARG.

   The descriptor is poised to read the data of the member
   when FUNCTION is called.  It does not matter how much
   data FUNCTION reads.

   If FUNCTION returns nonzero, we immediately return
   what FUNCTION returned.

   Returns -1 if archive does not exist,
   Returns -2 if archive has invalid format.
   Returns 0 if have scanned successfully.  */

long int
ar_scan(const char *archive, ar_member_func_t function, const void *arg)
{
#ifdef AIAMAG
    FL_HDR fl_header;
#ifdef AIAMAGBIG
    int big_archive = 0;
    FL_HDR_BIG fl_header_big;
#endif
#else
    int long_name = 0;
#endif
    char *namemap = 0;
    int desc = open(archive, O_RDONLY, 0);
    if(desc < 0)
        return -1;
#ifdef SARMAG
    {
        char buf[SARMAG];
        register int nread = read(desc, buf, SARMAG);
        if(nread != SARMAG || memcmp(buf, ARMAG, SARMAG)) {
            (void) close(desc);
            return -2;
        }
    }
#else
#ifdef AIAMAG
    {
        register int nread = read(desc, &fl_header, FL_HSZ);

        if(nread != FL_HSZ) {
            (void) close(desc);
            return -2;
        }
#ifdef AIAMAGBIG
        /* If this is a "big" archive, then set the flag and
           re-read the header into the "big" structure. */
        if(!memcmp(fl_header.fl_magic, AIAMAGBIG, SAIAMAG)) {
            big_archive = 1;

            /* seek back to beginning of archive */
            if(lseek(desc, 0, 0) < 0) {
                (void) close(desc);
                return -2;
            }

            /* re-read the header into the "big" structure */
            nread = read(desc, &fl_header_big, FL_HSZ_BIG);
            if(nread != FL_HSZ_BIG) {
                (void) close(desc);
                return -2;
            }
        } else
#endif
            /* Check to make sure this is a "normal" archive. */
        if(memcmp(fl_header.fl_magic, AIAMAG, SAIAMAG)) {
            (void) close(desc);
            return -2;
        }
    }
#else
    {
        int buf;
        register int nread = read(desc, &buf, sizeof(buf));
        if(nread != sizeof(buf) || buf != ARMAG) {
            (void) close(desc);
            return -2;
        }
    }
#endif
#endif

    /* Now find the members one by one.  */
    {
#ifdef SARMAG
        register long int member_offset = SARMAG;
#else
#ifdef AIAMAG
        long int member_offset;
        long int last_member_offset;

#ifdef AIAMAGBIG
        if(big_archive) {
            sscanf(fl_header_big.fl_fstmoff, "%20ld", &member_offset);
            sscanf(fl_header_big.fl_lstmoff, "%20ld", &last_member_offset);
        } else
#endif
        {
            sscanf(fl_header.fl_fstmoff, "%12ld", &member_offset);
            sscanf(fl_header.fl_lstmoff, "%12ld", &last_member_offset);
        }

        if(member_offset == 0) {
            /* Empty archive.  */
            close(desc);
            return 0;
        }
#else
        register long int member_offset = sizeof(int);
#endif
#endif

        while(1) {
            register int nread;
            struct ar_hdr member_header;
#ifdef AIAMAGBIG
            struct ar_hdr_big member_header_big;
#endif
#ifdef AIAMAG
            char name[256];
            int name_len;
            long int dateval;
            int uidval, gidval;
            long int data_offset;
#else
            char namebuf[sizeof member_header.ar_name + 1];
            char *name;
            int is_namemap;     /* Nonzero if this entry maps long names.  */
#endif
            long int eltsize;
            int eltmode;
            long int fnval;

            if(lseek(desc, member_offset, 0) < 0) {
                (void) close(desc);
                return -2;
            }
#ifdef AIAMAG
#define       AR_MEMHDR_SZ(x) (sizeof(x) - sizeof (x._ar_name))

#ifdef AIAMAGBIG
            if(big_archive) {
                nread = read(desc, &member_header_big,
                             AR_MEMHDR_SZ(member_header_big));

                if(nread != AR_MEMHDR_SZ(member_header_big)) {
                    (void) close(desc);
                    return -2;
                }

                sscanf(member_header_big.ar_namlen, "%4d", &name_len);
                nread = read(desc, name, name_len);

                if(nread != name_len) {
                    (void) close(desc);
                    return -2;
                }

                name[name_len] = 0;

                sscanf(member_header_big.ar_date, "%12ld", &dateval);
                sscanf(member_header_big.ar_uid, "%12d", &uidval);
                sscanf(member_header_big.ar_gid, "%12d", &gidval);
                sscanf(member_header_big.ar_mode, "%12o", &eltmode);
                sscanf(member_header_big.ar_size, "%20ld", &eltsize);

                data_offset = (member_offset + AR_MEMHDR_SZ(member_header_big)
                               + name_len + 2);
            } else
#endif
            {
                nread = read(desc, &member_header,
                             AR_MEMHDR_SZ(member_header));

                if(nread != AR_MEMHDR_SZ(member_header)) {
                    (void) close(desc);
                    return -2;
                }

                sscanf(member_header.ar_namlen, "%4d", &name_len);
                nread = read(desc, name, name_len);

                if(nread != name_len) {
                    (void) close(desc);
                    return -2;
                }

                name[name_len] = 0;

                sscanf(member_header.ar_date, "%12ld", &dateval);
                sscanf(member_header.ar_uid, "%12d", &uidval);
                sscanf(member_header.ar_gid, "%12d", &gidval);
                sscanf(member_header.ar_mode, "%12o", &eltmode);
                sscanf(member_header.ar_size, "%12ld", &eltsize);

                data_offset = (member_offset + AR_MEMHDR_SZ(member_header)
                               + name_len + 2);
            }
            data_offset += data_offset % 2;

            fnval =
                (*function) (desc, name, 0,
                             member_offset, data_offset, eltsize,
                             dateval, uidval, gidval, eltmode, arg);

#else /* Not AIAMAG.  */
            nread = read(desc, &member_header, AR_HDR_SIZE);
            if(nread == 0)
                /* No data left means end of file; that is OK.  */
                break;

            if(nread != AR_HDR_SIZE
#if defined(ARFMAG) || defined(ARFZMAG)
               || (
# ifdef ARFMAG
                      memcmp(member_header.ar_fmag, ARFMAG, 2)
# else
                      1
# endif
                      &&
# ifdef ARFZMAG
                      memcmp(member_header.ar_fmag, ARFZMAG, 2)
# else
                      1
# endif
               )
#endif
                ) {
                (void) close(desc);
                return -2;
            }

            name = namebuf;
            memcpy(name, member_header.ar_name, sizeof member_header.ar_name);
            {
                register char *p = name + sizeof member_header.ar_name;
                do
                    *p = '\0';
                while(p > name && *--p == ' ');

#ifndef AIAMAG
                /* If the member name is "//" or "ARFILENAMES/" this may be
                   a list of file name mappings.  The maximum file name
                   length supported by the standard archive format is 14
                   characters.  This member will actually always be the
                   first or second entry in the archive, but we don't check
                   that.  */
                is_namemap = (!strcmp(name, "//")
                              || !strcmp(name, "ARFILENAMES/"));
#endif /* Not AIAMAG. */
                /* On some systems, there is a slash after each member name.  */
                if(*p == '/')
                    *p = '\0';

#ifndef AIAMAG
                /* If the member name starts with a space or a slash, this
                   is an index into the file name mappings (used by GNU ar).
                   Otherwise if the member name looks like #1/NUMBER the
                   real member name appears in the element data (used by
                   4.4BSD).  */
                if(!is_namemap && (name[0] == ' ' || name[0] == '/')
                   && namemap != 0) {
                    name = namemap + atoi(name + 1);
                    long_name = 1;
                } else if(name[0] == '#' && name[1] == '1' && name[2] == '/') {
                    int namesize = atoi(name + 3);

                    name = alloca(namesize + 1);
                    nread = read(desc, name, namesize);
                    if(nread != namesize) {
                        close(desc);
                        return -2;
                    }
                    name[namesize] = '\0';

                    long_name = 1;
                }
#endif /* Not AIAMAG. */
            }

            sscanf(member_header.ar_mode, "%o", &eltmode);
            eltsize = atol(member_header.ar_size);

            fnval =
                (*function) (desc, name, !long_name, member_offset,
                             member_offset + AR_HDR_SIZE, eltsize,
                             atol(member_header.ar_date),
                             atoi(member_header.ar_uid),
                             atoi(member_header.ar_gid),
                             eltmode, arg);

#endif /* AIAMAG.  */

            if(fnval) {
                (void) close(desc);
                return fnval;
            }
#ifdef AIAMAG
            if(member_offset == last_member_offset)
                /* End of the chain.  */
                break;

#ifdef AIAMAGBIG
            if(big_archive)
                sscanf(member_header_big.ar_nxtmem, "%20ld", &member_offset);
            else
#endif
                sscanf(member_header.ar_nxtmem, "%12ld", &member_offset);

            if(lseek(desc, member_offset, 0) != member_offset) {
                (void) close(desc);
                return -2;
            }
#else

            /* If this member maps archive names, we must read it in.  The
               name map will always precede any members whose names must
               be mapped.  */
            if(is_namemap) {
                char *clear;
                char *limit;

                namemap = alloca(eltsize);
                nread = read(desc, namemap, eltsize);
                if(nread != eltsize) {
                    (void) close(desc);
                    return -2;
                }

                /* The names are separated by newlines.  Some formats have
                   a trailing slash.  Null terminate the strings for
                   convenience.  */
                limit = namemap + eltsize;
                for(clear = namemap; clear < limit; clear++) {
                    if(*clear == '\n') {
                        *clear = '\0';
                        if(clear[-1] == '/')
                            clear[-1] = '\0';
                    }
                }

                is_namemap = 0;
            }

            member_offset += AR_HDR_SIZE + eltsize;
            if(member_offset % 2 != 0)
                member_offset++;
#endif
        }
    }

    close(desc);
    return 0;
}


/* Return nonzero iff NAME matches MEM.
   If TRUNCATED is nonzero, MEM may be truncated to
   sizeof (struct ar_hdr.ar_name) - 1.  */

int ar_name_equal(const char *name, const char *mem, int truncated)
{
    const char *p;

    p = strrchr(name, '/');
    if(p != 0)
        name = p + 1;

    if(truncated) {
#ifdef AIAMAG
        /* TRUNCATED should never be set on this system.  */
        abort();
#else
        struct ar_hdr hdr;
        return strneq(name, mem, sizeof(hdr.ar_name) - 1);
#endif /* !AIAMAG */
    }

    return !strcmp(name, mem);
}

/* ARGSUSED */
static long int
ar_member_pos(int desc UNUSED, const char *mem, int truncated,
              long int hdrpos, long int datapos UNUSED, long int size UNUSED,
              long int date UNUSED, int uid UNUSED, int gid UNUSED,
              int mode UNUSED, const void *name)
{
    if(!ar_name_equal(name, mem, truncated))
        return 0;
    return hdrpos;
}

/* Set date of member MEMNAME in archive ARNAME to current time.
   Returns 0 if successful,
   -1 if file ARNAME does not exist,
   -2 if not a valid archive,
   -3 if other random system call error (including file read-only),
   1 if valid but member MEMNAME does not exist.  */

int ar_member_touch(const char *arname, const char *memname)
{
    long int pos = ar_scan(arname, ar_member_pos, memname);
    int fd;
    struct ar_hdr ar_hdr;
    int i;
    unsigned int ui;
    struct stat statbuf;

    if(pos < 0)
        return (int) pos;
    if(!pos)
        return 1;

    fd = open(arname, O_RDWR, 0666);
    if(fd < 0)
        return -3;
    /* Read in this member's header */
    if(lseek(fd, pos, 0) < 0)
        goto lose;
    if(AR_HDR_SIZE != read(fd, &ar_hdr, AR_HDR_SIZE))
        goto lose;
    /* Write back the header, thus touching the archive file.  */
    if(lseek(fd, pos, 0) < 0)
        goto lose;
    if(AR_HDR_SIZE != write(fd, &ar_hdr, AR_HDR_SIZE))
        goto lose;
    /* The file's mtime is the time we we want.  */
    EINTRLOOP(i, fstat(fd, &statbuf));
    if(i < 0)
        goto lose;
#if defined(ARFMAG) || defined(ARFZMAG) || defined(AIAMAG) || defined(WINDOWS32)
    /* Advance member's time to that time */
    for(ui = 0; ui < sizeof ar_hdr.ar_date; ui++)
        ar_hdr.ar_date[ui] = ' ';
    sprintf(ar_hdr.ar_date, "%ld", (long int) statbuf.st_mtime);
#ifdef AIAMAG
    ar_hdr.ar_date[strlen(ar_hdr.ar_date)] = ' ';
#endif
#else
    ar_hdr.ar_date = statbuf.st_mtime;
#endif
    /* Write back this member's header */
    if(lseek(fd, pos, 0) < 0)
        goto lose;
    if(AR_HDR_SIZE != write(fd, &ar_hdr, AR_HDR_SIZE))
        goto lose;
    close(fd);
    return 0;

  lose:
    i = errno;
    close(fd);
    errno = i;
    return -3;
}


#ifdef TEST

long int
describe_member(int desc, const char *name, int truncated,
                long int hdrpos, long int datapos, long int size,
                long int date, int uid, int gid, int mode, const void *arg)
{
    extern char *ctime();

    printf(_("Member `%s'%s: %ld bytes at %ld (%ld).\n"),
           name, truncated ? _(" (name might be truncated)") : "",
           size, hdrpos, datapos);
    printf(_("  Date %s"), ctime(&date));
    printf(_("  uid = %d, gid = %d, mode = 0%o.\n"), uid, gid, mode);

    return 0;
}

int main(int argc, char **argv)
{
    ar_scan(argv[1], describe_member, NULL);
    return 0;
}

#endif /* TEST.  */
#endif /* NO_ARCHIVES.  */
